Grouser shoes are attached to interconnected links making up the flexible track of a vehicle such as a crawler tractor or the like. The shoes provide the tractor with both floation and traction. Since a tractor usually utilizes 62 to 86 grouser shoes, and since these shoes are subjected to rapid wear, the cost of grouser shoe replacement is very significant.
Each grouser shoe includes a relatively flat pad area having means for attaching it to a track chain or rail assembly upon the vehicle, thereby facilitating a controlled relative movement between adjacent pads. The primary purpose of the pad area is to provide floation.
A bar is affixed to one surface of the pad either as an integral part thereof or as a component manufactured separately and welded to the pad. It extends outward from the surface, its length being disposed across the width of the pad such that during tractor operation the bar is forced against or into the earth being traversed. The bar is the first portion of the shoe subjected to serious wear, particularly when the equipment is operating in hard or rocky terrain. Since grouser shoes are extremely expensive, it is the normal and desirable practice to replace worn bars by welding new bars to the pads, thereby increasing the shoe life.
Weldable grouser bars and similar parts have been manufactured and used in the past. However, they have usually been of a substantially uniform hardness over their entire widths and of uniform cross-sectional configuration over their entire lengths such as shown in U.S. Pat. Nos. 1,952,545 and 3,307,882, for example. Configurations such as these have been difficult to adapt to worn surfaces in view of the fact that standard grouser bars wear with a distinctive, but relatively predictable curvation across their central region. There is also a marked increase in wear over the last few inches adjacent to the ends since this region is subjected to maximum abrasion in turns and the like. The greatest part of the central region, being of a thickness and hardness fairly uniform with the rest of the bar, is a typically relatively flat, although angled, with a rapidly "dubbed-off" corner. Hence, when repaired with a standard replacement bar, a great amount of filler weldment is required to close the gaps between the worn bar and the replacement bar. Additionally, while it is recognized that tip hardening has been accomplished in original, integral construction, as shown in U.S. Pat. Nos. 1,602,199 and 2,549,930, the requirement to obtain weldability in replacement bars has generally resulted in a compromise in wear characteristics, since softness for weldability and hardness for maximum wear have heretofore basically been features of incompatibility in a single replacement bar. Additionally, other than by, perhaps, providing a cast and forged bar, there has been no adequate method to obtain replacement grouser bar with thickened ends for maximizing wear in such vulnerable regions. More particularly, there has been no means for obtaining such results when starting from flat stock, as in the present invention.